Mechanism for producing welts on straight bar knitting machines



Jan. 3, 1939. L, H, coLTog. 2,142,745

MECHANISM FOR PRODUCING WELTS ON STRAIGHT BAR KNITTING MACHINES FiledJune 15, 1938 s Sheets-Sheet 1 L717 Fig. 2.

Jan. 3, 1939. L. H. COLTON 2,142,745

MECHANISM FOR PRODUCING WELTS ON STRAIGHT BAR KNITTING MACHINES FiledJune 15, 1938 5 SheetsSheet 2 INVENTOR.

A TTOENEY Jan. 3, 1939. L. H. COLTON 2,142,745

MECHANISM FOR PRODUCING WELTS ON STRAIGHT BAR KNITTING MACHINES FiledJune 15, 1938 5 Sheets-Sheet '3 Fig.10.

INVENTOR Patented Jan. 3, 1939 I PATENT OFFICE MECHANISM FOR PRODUCINGWELTS ON STRAIGHT BAR KNITTING MACHINES Lewis Henry Colton, WestBridgford, Nottingham, England Application June 15, 1938, Serial No.213,899 In Great Britain June 18, 1937 14 Claims. (01. 6696) Thisinvention comprises improvements in mechanism for producing welts onstraight bar knitting machines, such as machines of the Cottons patenttype.

. More particularly the invention relates to means for producing a weltin a fully automatic manner and refers to welting mechanism of the kindwherein welt hooks are operated from above the frame needles toreceiveloops released from said needles or extending between spacedneedles and subsequently after the formation of the requisite welt toreturn such loops to or place them on the needles, said welt hooks beingprovided on a welt bar carried by depending arms that are guided againstundesirable lateral movement and said welt bar being operated from a camshaft located above the needle row.

In welting mechanism of this kind, as hitherto operated, the welt hooksare lowered at the front side'of the needles (i. e. at the bearded sidethereof which is at the back of the line of needles from the machineoperator) in contact with the presser bar and serve to press the beardof every second needle, so that as the needles are lowered every secondloop is cast off. The welt hooks now move towards the front of themachine, over the heads of the needles so that each hook is entered intoa loop that extends between say two even needles over two knocking-overbits, and upon further downward movement of the welt hooks the point ofeach hook is brought below the loop that said hook engages, so that saidloop is securely landed in the hook. In this mode of operation it isessential that the welt bar, on which the hooks are mounted, be soadjusted that the hooks pass across the line of needles in closeproximity to the needle heads, and this is diflicult, particularly as itis customary to adjust the needle bar to govern the'quality of thefabric and each such adjustment throws the welt bar out, of adjustment.As a result, there is alwaysa danger that the welt hooks will foul theneedle heads (which are not always perfectly aligned) or will pass overthem at too great a distance from them and there is a danger'of needlebreakage by reason of faulty positioning of the welt hooks. Moreover,the use of the welt books as pressing-instruments itself involvesdifficulties in the design and adjustment or setting of the hooks.

An object of the invention is to simplify and render particularlyefficaciou's automatic weling by the employment of mechanism of the kindreferred to. The present invention provides .a method of producing aturn-over welt on a straight bar knitting machine by the employment ofwelting mechanism of the kind. referred to, wherein the thread of thefirst course is prevented, by means independent of the welt hooks, frombeing engaged in the beards of spaced needles with which the Welt hooks.co-operate. Selected or predetermined thread loops, to be received bythe welt hooks, may be released from the needles by said means.Alternatively, the thread for said initial welt course is laid on orreceived by selected or predetermined needles only, so as to providebetween said selected needles floating thread portions adapted to betaken up by the welt hooks and carried thereby during the weltproduction.

Viewing the invention from another aspect same comprises a method ofproducing a turnover welt by the mechanism previously mentioned whereinthe loops to be taken by the welt hooks are released or pressed-off fromselected needles (e. g. alternate needles) by pressing said selectedneedles while said hooks are maintained out of contact with and abovethe needles and during the downward movement of the needle bar, thehooks being subsequently lowered to receive the released loops prior toproceeding with the production of the welt.

Viewing the invention from another aspect same resides in effecting therelease or press-ofi of the loops to be taken by the welt hooks, by theco-operation with selected needles (alternate needles) of points orequivalent elements which are projected down to take the loops from thenee- .dles while said needles are being lowered and while the welt hooksare retained above the needles.

The invention also includes welting mechanism of the kind referred to,having means independent of the welt hooks for preventing the thread ofthe first welt course from being engaged in the beards of spaced needleswith which the welt hooks co-operate, said thread being engaged in thehooks of the intervening needles.

In order that the invention may be better understood, reference will nowbe made to the accompanying drawings, in which Figure 1 is a sectionalelevation showing, the relevant parts of the welting mechanism, and theneedles and sinkers; Figures 2-7 show various stages in the operation ofsaid mechanism;

Figure 8 is a scrap section and Figure 9 a plan, partly broken away, ofa presser arrangement that may be employed;

Figure 10 illustrates the use of pressing instructions mounted above theneedle row; while Figures 11 and 12 illustrate two alternativearrangements of needle bars.

Referring now particularly to Figs. 1-7, the welt transfer mechanism,which is driven in coordination with the needle movements, is mountedabove the knitting mechanism of the machine and above the customarynarrowing mechanism (indicated at I24). The said welt mechanismcomprises welt bars l0 (one for each division) each carried by andextending between the lower ends of a pair of depending arms II, andeach bar being provided with the requisite number of downwardlyprojecting welt hooks l2, one hook for every other frame needle. Thedepending arms ll carrying the welt bars have associated therewith attheir upper ends link or lever mechanism with cam trucks or rollerscoacting with the'peripheral faces of cams (indicated generally at l3and I4) mounted on a cam shaft I5, rotation being imparted to said camshaft (5 at the required times from the main shaft l6 of the machine orother suitable working shaft through the intermediary of a clutch or thelike (not shown). The cams l4 function to impart vertical movement tothe welt bars I0 through the medium of swinging arms ll (from which thearms ll hang at l9) and trucks l8 and the cams I3 function to impartbackward and forward movement'thereto. For this purpose spring-biasedlevers 20, attached to the arms II, project rearwardly from the pivot l9whereby said arms II are pivoted to the swinging arms l1, and saidlevers 20 are provided with trucks 2|. The welt hooks l2 are, at therequired time, lowered to receive from alternate ones of the frameneedles 22 loops appertaining to the first welt course, and then raisedsufliciently to hold said loops while the welt is knitted. During theknitting of the welt the cams 13 are rotated so as to permit the springsto rock the dependingarms II to carry the weltbars l0 outwardly in frontof the needles to a predetermined distance and back again, and whilethis is being accomplished the usual welt rods are inserted in the knownmanner and are connected up to the fabric take-up. After the welt isknitted the welt hooks are caused to assume a position over the needlesso that the alternate needles from which the loops were previouslyreleased are caused, .on their upward movement, to pierce the loops ofthe first welt course carried by the hooks said hooks having impartedthereto a vertical motion so as to transfer the loops therefrom tothe'needles. Particularly during the reception from, and the restoration to,the needles, of the loops of the first welt course the welt bars ID areguided against undesirable endwise movement by guides 23.

The mechanism as so far described is substantially similar to thatdescribed in British patent specification No. 476,045, to whichreference may be made for further details thereof. It may here beemphasized, however, that according to the present invention themechanism is operated,

during the actual receptiton of the loops, in a manner different to thatdescribed in the aforesaid patent specification. According to the saidspecification, the welt hooks are first lowered at the bearded side ofthe needles to press alternate frame needles and to receive the loopstherefrom. In the exercise of the present invention the welt hooks arenot employed to press the needles and hence are not first inserted atthe beard side of said needles; on the contrary of spaced (e. g.alternate) needles when the needle bar 24 is lowered. Therefore theloops on said needles are pressed off, that is tosay said loop areprevented from entering or passing under the beards but are caused, onthe downward movement of the needles, to be cast off prior to beingtaken up by the welt hooks I2, the cast off loops being picked up bysaid welt hooks from the knocking-over bits 25 .by which the cast offloops are received. One method in accordance with this invention ofreleasing the loops from the frame needles is by projecting Y at therequired time between the front face of the presser bar 26 and thealternate needles, presser elements 21 (Fig. 2) which function to pressthe needle beards and maintain same pressed during the downward movementof the needles for a sufficient time to permit of the loops being passedover the beards, after which 'said presser elements are withdrawn.

Thus the stage shown in Fig. 3 is reached, the loops having been pressedoff from, say, every odd needle so that each pressed-off loop extendsbetween a pair of unpressed even needles over a pair of knocking-overbits 25, so that the welthooks 12 may readily be lowered behind the oddneedles to transfix said loops. In Fig. 4 a welt hook is shown justentering such a loop, while in Fig. 5 the hook is shown as havingcompletely transfixed the loop.- As will readily be under-. stood, ifthe hook is now raised, the loop is passed down into the bight of it,where it is securely retained. Thereafter the knitting of the weltproceeds, the welt hooks being gradually moved away from the needles, asshown in Fig. 6, to take up the fabric produced. At a certain stage awelt-rod is inserted and connected to the customary draw-off straps androllers (not shown). At the completion of thewelt the welt rod isremoved, and rotation of the cam shaft l5 brings the welt hooks to theposition shown in Fig. '7 (which figure shows one of the needles whichwas pressed oil. at the commencement of the welt, (e. g. an odd needle)in which they are slightly above and slightly to the front side of theneedles. The needles now rise, to transfix the loops held on thewelt-hooks, and in their upward movement the beard of each needle movesup the groove in the face of the short limb of the associated welt-hook.During the last part of the upward movement of the needles 4 Thereafter.rotation of cam-shaft I5 ceases .and

the whole welting mechanism may be swung upwards to an inoperativeposition.

These presser elements operating at alternate individual needles arecarried by a suitable bar to which the requisite motion is imparted fromany suitable source, conveniently from the main cam shaft of themachine, or from the shaft or other member which controls or impartsautomatic movements in the machine;

In the construction illustrated in Fig. "1, the presser elements 21 arecarried by a bar 28 arranged to be raised and lowered by levers 29 and30, rocking about pivot 34, and a truck 3| 00- operating with a cam 32on-the main cam-shaft I 6. This truck 3| is shiftable by means indicatedat 33 (and conveniently controlled from the main chain of the machine orfrom any suitable control device) to bring it, at the appropriate times,into register either with the cam 32 or with a plain, circular, discalongside it, it being understood that when the truck engages the discthe bar 28 is not moved.

As the bar 28 is raised the presser elements 21 are advanced towards theneedles 22 by means of parts I34 on the machine frame cooperating withinclined faces 35 on the arms 36 by which said bar is connected to thelevers 29.

The presser elements may be resilient, and means may be provided fordeflecting them towards the needles as said elements are moved in thedirection of their length (e. g. as they are raised). In an alternativearrangement (Figs. 8 and 9) the pressing of the alternate needles forreleasing the loops therefrom may be effected by providing presserelements 31 on the front face of the presser bar 26 and imparting tosaid elements a horizontal reciprocating movement to and from theneedles (by means not shown, but readily understood by one skilled inthe art); while in a further arangement depending presser elements maybe carried by a bar located above the needles so as to effect thepressing of the beards by a simple vertical motion.

Thus as shown in Fig. 10, depending points 21 carried by a point barlocated above the needles like a picot bar, and appertaining toalternate needles may be operated to descendat the bearded side of saidalternate needles, press the beards thereof, receive the loops from saidneedles and subsequently release said loops on to the knockingover bits,the loops thus released being subsequently picked up by the welt hooks.

In a still further alternative arrangement the frame needles of themachine may be so mounted that alternate needles can be projected to agreater height than the remaining alternate needles, in which case thecustomary needle presser may at the required time function to pressalternate needles for releasing therefrom the loops to be suspended uponthe welthooks.

In a further arrangement, Fig. 11, the thread for the first welt courseis laid on the shanks of alternate needles only. For this purposealternate needles are mounted in two needle bars 24 and 24 so that bymoving the bar 24 every second needle may be moved to an inoperativeposition. For example the two bars may be pivoted at 38, so that one setof needles may be swung away from the other set. Alternatively, as shownin Fig. 12 one of the bars 24a or 24b, may be raised and lowered inrelation to the other bar so that, at the time when the thread of theinitial welt course is laid, the needles thereof are located below thefeed level. In such an arrangement it is obvious that thread will onlybe taken by, say, the even needles at the first course, and after theseneedles have moved down to take the thread in their beards, the threadportions extending between said needles arepicked up by the welt hooksfrom the knocking-over bits. At the next thread feed all the needles arebrought to the same level so, that all take thread, all of the needlescontinuing to operate throughout the welt; and on completing the welt,loops held by the hooks are transferred to the aforesaid odd needles.

It may be found unnecessary to displace alterhate needles (odd needles)completely below the thread feeding level, but in any case the extent ofIt is to be understoood that the invention is not limited to theparticular methods hereinbefore described of releasing stitch loops fromthe frame needles at the first welt course, as other means independentof the welt hooks may be employed for accomplishing this.

I claim:-

1. In welting mechanism of the kind having welt hooks operable fromabove the needles to receive loops therefrom and subsequently, after theformation of the welt to place said loops on the needles, said welthooks being provided on a welt bar carried by depending arms guidedagainst undesirable lateral movements, and a cam shaft for operating thewelt bar located above the needles; means, independent of the welthooks, for preventing the thread of the initial welt course from beingengaged in the hooks of spaced needles, for reception by the welt hooks,said thread being engaged in the hooks of intervening needles.

2. In welting mechanism of the kind having welt hooks operable fromabove the needles to receive loops therefrom and subsequently, after theformation of the welt to place said loops on the needles, said welthooks being provided on a welt bar carried by depending arms guidedagainst undesirable lateral movements, and a cam shaft for operating thewelt bar located above the needles; means, independent of the welthooks, for releasing from the needles the loops that are to be receivedby said hooks.

3. Mechanism according to claim 2, wherein said independent meanscomprises presser elements for pressing of the loops.

4. In welting mechanism of the kind having welt hooks operable fromabove the needles to receive thread kinks of the initial welt course andsubsequently to place said kinks on the needles after the formation ofthe requisite-welt courses, which welt hooks are mounted on a welt barcarried by depending arms and guided against undesired lateral movement,and a cam located above the needles for operating the welt bar; thecombination of means, independent of said hooks, for preventing thereceptionin the hooks of spaced needles of the thread of theinitialcourse, and means for inserting the welt hooks at the plain side of theneedles to receive the thread kinks extending between the interveningneedles;

'5. In welting mechanism of the kind having welt hooks operable fromabove the needles to receive thread kinks of the initial welt course andsubsequently to place said kinks on the needles after the formation ofthe requisite welt courses, which welt hooks are mounted on a welt barcarried by depending arms and guided against undesired lateral movement,and a cam located above the needles for operating the welt bar; thecombination of knocking over bits, presser means independent of the welthooks for pressing off spaced kinks onto said bits, and

means for inserting the welt hooks at the plain side of the needles toreceive said pressed-off kinks.

6. Mechanism according toclaim 2, wherein 7 said independent meanscomprises presser instruments, and a bar below the needles on which saidinstruments are mounted.

7. Mechanism according to claim 2, wherein the said independent meanscomprises a presser bar for pressing oil the loops from spaced needles.

8. In a straight bar knitting machine havin a line of bearded needlesand thread-laying means, said needles being movable in the direction oftheir length to knit, welting mechanism comprising a welt bar, welthooks thereon for spaced needles, depending arms carrying said bar, asupport for said arms, means independent of said welt hooks for causingsaid spaced needies to miss the thread of an initial welt course upondescent of the needles, and means, including cam mechanism mounted abovethe needles, for inserting the welt hooks at the plain side of saidspaced needles to receive the thread portions missed thereby and, afterthe formation of the requisite number of welt courses, to restore saidthread portions to the spaced needles.

9. In the combination according to claim 8, means, included in said cammechanism, for pcsitioning the welt hooks at the hook side of theneedles to restore the thread portions thereto.

10. In a knitting machine, mechanism according to claim 1, and means formoving spaced needles to a position wherein they do not receive thethread of an initial welt course, said thread being received onintervening needles.

11. Mechanism according to claim 2, wherein said independent meanscomprises presser instruments for pressing oi! thread of the initialcourse from spaced needles and for receiving the pressed-oi! thread.

12. In a straight bar knitting machine having a line of bearded needlesand thread-laying means, said needles being movable in the direction oftheir length to knit, welting mechanism comprising a welt bar, welthooks thereon. for spaced needles, depending arms carrying said bar,

a support for said arms, knocking over bits, pressers extending upbetween the said bits, a

mounting for said pressers below said bits, means for operating saidpressers to press spaced needles to cast of! spaced kinks of an initialwelt course, and means, including cam mechanism mounted above theneedles, for inserting the welt hooks at the plain side of said spacedneedles to receive the thread portions missed thereby and, after theformation, of the requisite number of welt courses, to restore saidthread portions to the spaced needles.

13. A method of producing a turn-over welt on a knitting machine, havinghooked needles and means for preventing the reception of portions of aninitial welt course in the hooks of spaced needles, by the employment ofwelting mechanism of the kind having welt hooks operable from above theneedles to receive thread portions of said initial course andsubsequently toofler said loops to the needles, said welt hooks beingprovided on a welt bar carried by depending arms and guided intoregister with the needles, cam mechanism located above the needles foroperating the welt hooks, which method comprises lowering the welt hooksat the plain side'of said spaced needles to receive said threadportions, and subsequently locating the hooks at the hooked side of theneedles to ofler said thread portions to the needles.

14. A method of producing a turn-over welt,

on a. knitting machine having bearded needles, by the employment ofwelting mechanism of the kind comprising a support, arms dependingtherefrom, a welt bar carried by said arms, welt hooks for spacedneedles carried by said bar, means for restraining endwise movement ofsaid bar, and cam mechanism located above the needles for operating thehooks to receive thread portions of an initial welt course extendingacross said spaced needles and subsequently to ofler said portions tosaid needles, which method com-- prises the step of preventing, by theuse of means independent 0! the welt hooks, the thread of said initialcourse from being engaged in the beards 0! said spaced needles.

LEWIS HENRY COL-TON.

